Vacuum-ultraviolet photochemistry. VII - Photolysis of hydrazine-15N in the presence of 14NO at 1470 angstrom
Molecular elimination and disproportionation effects on formation of nitrogen in hydrazine and hydrazine 15 photolysis
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Hydrazine inactivates bacillus spores
Planetary Protection places requirements on the maximum number of viable bacterial spores that may be delivered by a spacecraft to another solar system body. Therefore, for such space missions, the spores that may be found in hydrazine are of concern. A proposed change in processing procedures that eliminated a 0.2 um filtration step propmpted this study to ensure microbial contamination issue existed, especially since no information was found in the literature to substantiate bacterial spore inactivation by hydrazine.
Bacillus↗
NASA Engineering and Safety Center Technical Bulletin No. 20-08: Assessment of Ketazine Derived High Purity Hydrazine for Spacecraft Propellant Systems
Hydrazine and its derivatives have dominated the class of hypergolic liquid propellants for bipropellant propulsion systems in rockets such as the Titan, MX Missile, and Ariane; it has also been widely utilized as a monopropellant in auxiliary power units and in thrusters for altitude and in-orbit control of satellites and spacecraft. With continued use of hydrazine in current and future spacecraft and payloads, it is necessary to understand the historical and current states of synthesis for the commodity and possible implications that may arise from changes in production processes for the United States stock.
Ketazine↗
NASA Engineering and Safety Center Technical Bulletin No. 22-08; Contaminant Reduction in High Purity Hydrazine
Hydrazine and its derivatives are used ubiquitously in liquid propulsion systems. In smaller thruster systems, contaminant build up has historically caused flow decay and consequently performance losses. Many of these contaminants are not controlled by the current revision of MIL-PRF-26536 [1], the High Purity Hydrazine (HPH) procurement specification, yet have been observed to be present in HPH at variable concentration and, often exceed potentially problematic levels for small thrusters. This technical bulletin outlines recent work aimed at identifying appropriate separation processes to remove specific target elemental and carbonaceous contamination in HPH.
Technical Bulletin No. 22-08↗
Trace hydrazines in aqueous solutions accurately determined by gas chromatography
Trace amounts of hydrazines in aqueous solutions can be determined by using polythyleneimine /PEI/ in conjunction with the gas chromatographic column. The PEI specifically retains water without altering the separability or elution order of the hydrazine and associated constituents.
Welz, E. A., Jr.↗
Study of hydrazine reactor vacuum start characteristics Quarterly progress report, 1 May - 31 Jul. 1969
Liquid hydrazine penetration into catalyst particles upon immersion and decomposition of hydrazine gas
Kesten, A. S.↗
Effects of sterilization and decontamination on hydrazine propulsion systems.
Catalyst poisoning and hydrazine material compatibility during hydrazine propulsion systems sterilization and decontamination
Heinz, M. H.↗
Experimental evaluation of high-thrust, throttleable, monopropellant hydrazine reactors
Throttleable monopropellant hydrazine catalytic reactors of a size applicable to a planetary landing vehicle were designed, fabricated, and tested. An experimental evaluation of two 2670-N reactor designs was conducted. The steady state and dynamic characteristics of the thruster/valve combinations were determined. The results of the testing, including the engine characteristic velocity, smoothness of combustion, insensitivity to heat sterilization, and response during various simulated duty cycles are presented and discussed. No problems of a fundamental nature were encountered as a result of rapid dynamic throttling of these large hydrazine reactors.
Riebling, R. W.↗
Monopropellant hydrazine resistojet preliminary design task
The design effort for the electrothermal hydrazine thruster (ETH) is summarized. The EHT decomposes hydrazine thermally and expands the decomposition products through a nozzle to provide the impulse necessary to fulfill spacecraft propulsive requirements. The thruster is capable of operation at pulse widths from 0.050 second to steady state and delivers specific impulse values from 175 to greater than 225 seconds, depending upon the duty cycle. The design of the EHT is the result of an analytical effort combined with a series of design verification tests. The design requirements, design philosophy and detailed design methods are outlined. A discussion of the rationale behind the selection of materials for the EHT is included. The results of the design verification tests are also presented.
Murch, C. K.↗
A portable hydrazine attitude propulsion test system
The portable hydrazine attitude propulsion module is described that was designed and developed to support the attitude control pitch axis simulation tests performed on an air bearing table for the thermoelectric outer planet spacecraft program. The propulsion module was a self-contained, liquid hydrazine propulsion system from which the exhausted gases were generated within the catalyst bed of either of two nominal 0.22-N opposing thrusters. The module, which was designed for convenient assembly onto and removal from an air bearing table, was tested to establish its operational safety. This test history and the very conservative design of the module enabled it to be man-rated for operation in the presence of personnel. The report briefly summarizes the system operations during air bearing table tests, presents a detailed description of the propulsion module hardware, and discussing the system evolution.
Moynihan, P. I.↗
Rubber composition compatible with hydrazine
Formulation improves compatibility of butyl rubbers with hydrazine while reducing permeation to low levels necessary for prolonged storage in space. This is accomplished by replacing carbon-black filler with inert materials such as hydrated silica or clay. Pressure increases suggest that hydrazine is decomposed only slightly by new type of rubber.
Repar, J.↗
Biological effects of fuel and exhaust components from spacecraft descent engines employing hydrazine
The effect of the products of the Viking terminal descent engine fuel upon possible extraterrestrial life at the Martian landing site is examined. The effects of the engine exhaust, the hydrazine fuel, and the breakdown products of the latter on terrestrial microorganisms have been studied. The results indicate that the gaseous exhaust products would probably not be hazardous to microorganisms, but that liquid hydrazine would be lethal.
Lehwalt, M. E.↗
Monolithic catalyst beds for hydrazine reactors
A monolithic catalyst bed for monopropellant hydrazine decomposition was evaluated. The program involved the evaluation of a new hydrazine catalyst concept wherein open-celled foamed materials are used as supports for the active catalysts. A high-surface-area material is deposited upon the open-celled foamed material and is then coated with an active metal to provide a spontaneous catalyst. Only a fraction of the amount of expensive active metal in currently available catalysts is needed to promote monolithic catalyst. Numerous parameters were evaluated during the program, and the importance of additional parameters became obvious only while the program was in progress. A demonstration firing (using a 2.2-Newton (N)(0.5-lbf) reactor) successfully accumulated 7,700 seconds of firing time and 16 ambient temperature starts without degradation. Based on the excellent results obtained throughout the program and the demonstrated life capability of the monolithic foam, it is recommended that additional studies be conducted to further exploit the advantages of this concept.
Source record↗
Rubber compositions for hydrazine service
Forty-three compounds were formulated and tested for physical properties and hydrazine compatibility. Variables introduced include silicon dioxide filler loading level and particle size. Both butyl and ethylene-propylene rubbers were employed as well as various vulcanization systems. The data showed that compounds containing butyl and butyl blended with ethylene propylene could not be distinguished from ethylene propylene alone as far as chemical properties were concerned. A trend noted was that a filler level with higher silicon dioxide loading exhibited better hydrazine compatibility. Particle size variation did not show any consistent trends. Any of the vulcanization systems employed appeared to be satisfactory. A refined technique for dissolving aluminum cores from EPT-10 bladders was also tested.
Repar, J.↗
Monopropellant hydrazine resistojet: Data correlation
The design, development, and testing of an engineering model nominal 20-millipound thrust monopropellant hydrazine resistojet program is divided into six basic tasks. Included in these tasks are analyses, design, test, and data correlation of the electrothermal hydrazine thruster (EHT). A brief summary is provided of the analyses conducted for the EHT and the design of the engineering model thruster. Some of the results of the engineering model tests are then compared with the analytical performance models generated early in the program.
Murch, C. K.↗
Long-time dynamic compatibility of elastomeric materials with hydrazine
The tensile property surfaces for two elastomeric materials, EPT-10 and AF-E-332, were generated in air and in liquid hydrazine environments using constant strain rate tensile tests over a range of temperatures and elongation rates. These results were used to predict the time-to-rupture for these materials in hydrazine as a function of temperature and amount of strain covering a span of operating times from less than a minute to twenty years. The results of limited sheet-folding tests and their relationship to the tensile failure boundary are presented and discussed.
Coulbert, C. D.↗
Sustained load crack growth design data for Ti-6Al-4V titanium alloy tanks containing hydrazine
Sustained load crack growth data for Ti-6Al-4V titanium alloy in hydrazine per MIL-P-26536 and refined hydrazine are presented. Fracture mechanics data on crack growth thresholds for heat-treated forgings, aged and unaged welds, and aged and unaged heat-affected zones are reported. Fracture mechanics design curves of crack growth threshold stress intensity versus temperature are generated from 40 to 71 C.
Lewis, J. C.↗
Absolute rate parameters for the reaction of atomic hydrogen with hydrazine
Absolute rate parameters for the reaction of atomic hydrogen with hydrazine H + N2H4 yields H2 + N2H3 have been determined in a direct manner using flash photolysis of dilute mixtures of hydrazine in helium and time dependent observation of H via resonance fluorescence. By measuring the H-atom decay under pseudo-first-order conditions, the bimolecular rate constant K sub 1 was obtained over the temperature range 228-400 K. The data were fitted with good linearity to the Arrhenius expression K sub 1 = (9.87 plus or minus 1.17) x 10 to the -12th exp(-2380 plus or minus 100/RT) cu cm/molecule/s. The data were shown to be free of any contributions from secondary reactions involving H as a reactant or product.
Stief, L. J.↗